1. Field of the Invention
The present invention relates to a printing apparatus.
2. Description of the Related Art
Conventionally, in a printing apparatus having a sheet feeding mechanism, a sheet conveying mechanism, a carriage mechanism and the like, in order to provide a high printing speed and simplify the mechanisms, a dedicated motor or the like is provided for driving each of the mechanisms and operating each of the mechanisms at an optimum timing.
In the above-described conventional approach, however, the number of motors which are simultaneously driven increases, thereby increasing, for example, the peak electric power, the size of the power supply and the size of the apparatus. That is, in order to achieve high-speed printing, a method has been adopted in which feeding of a succeeding sheet of a recording medium is started before discharging a preceding sheet of the recording medium, using a plurality of motors. In this method, since a sheet feeding operation and a sheet discharging operation are performed in a state of being partially overlapped, the total throughput can be shortened. However, this method results in a large increase in the used electric power, so that the capacity of the power supply must be designed so as to coincide with the maximum electric power, thereby increasing, for example, the size of the power supply and the size of the apparatus, as described above.
The present invention has been made in consideration of the above-described problems.
It is an object of the present invention to provide a printing apparatus which can perform high-speed recording with lower electric power by optimizing the distribution of electric power for a plurality of driving sources.
According to one aspect, the present invention which achieves the above-described object relates to a printing apparatus for performing printing on a printing medium using a print head. The printing apparatus includes printing medium feeding means, driven by electric power, for feeding the printing medium in a direction toward the print head before performing printing, electric-power control means for controlling electric power for driving the printing medium feeding means, at least one electric-power using source other than the printing-medium feeding means, and determination means for determining a state of use of electric power of the at least one electric-power using source, when driving the printing medium feeding means. The electric-power control means controls electric power for driving the printing-medium feeding means, based on a result of determination of the determination means.
According to another aspect, the present invention which achieves the above-described object relates to a method for controlling electric power in a printing apparatus for performing printing on a printing medium using a print head. The method includes a printing medium feeding step, utilizing a printing medium feeding unit driven by electric power, for feeding the printing medium in a direction toward the print head before performing printing, and a determination step for determining a state of use of electric power by components other than the printing medium feeding unit, when executing the printing medium feeding step, the other components being executable simultaneously with the printing-medium feeding step. A magnitude of electric power used by the printing medium feeding unit in the printing-medium feeding step is controlled in accordance with a result of the determination in the determination step.
According to yet another aspect of the present invention, a printing apparatus for performing printing on a printing medium using a print head includes a printing medium feeding unit, at least one electric-power using source other than the printing medium feeding unit, and a controller. The printing medium feeding unit feeds the printing medium in a direction toward the print head before performing printing, and is driven by electric power. The controller controls the electric power for driving the printing medium feeding unit and the at least one electric-power using source. The controller determines a state of use of electric power of the at least one electric-power using source, when driving the printing medium feeding unit. The controller controls electric power for driving the printing medium feeding unit, based on a result of determination regarding the state of use of electric power.
In this specification, the word xe2x80x9cprintingxe2x80x9d indicates not only a case of forming significant information comprising characters, drawings and the like, but also a case of forming information comprising images, figures, patterns and the like on a printing medium, or processing the printing medium, whether or not the information is significant or insignificant, and whether or not the information is visualized so as to be sensed by the human being.
The terms xe2x80x9cprinting mediumxe2x80x9d indicates not only paper used in an ordinary printing apparatus, but also a substance which can receive ink, such as a cloth, a plastic film, a metal plate or the like.
The word xe2x80x9cinkxe2x80x9d is to be as widely construed as the above-described definition of xe2x80x9cprintingxe2x80x9d, and indicates a substance which can be used for forming images, figures, patterns and the like on a printing medium, or processing of the printing medium by being provided onto the printing medium.